To assist in the prediction of performance trends of catalyst used in fuel cells, activity and durability of catalysts can be measured in an electrochemical cell. Typically, the catalyst is tested as a thin-film cast on a rotating disk electrode. The optimum results are obtained when the thin-film is uniform across the surface of the disk with no surface irregularities. Conventional procedures to prepare the electrodes do not result in a uniform thin-film, thus reducing the accuracy of the testing results.